Exemplary embodiments relate generally to a method of forming a semiconductor device and, more particularly, to a method of forming a semiconductor device that is capable of finely forming the patterns of the semiconductor device by overcoming an exposure resolution limit.
In a common semiconductor device formation process, a hard mask pattern is formed on a base layer (for example, a silicon layer, an insulating layer, or a conductive layer) including a predetermined etch target layer for forming a pattern. The base layer is etched by an etch process using the hard mask pattern as an etch mask pattern, to form the patterns of the semiconductor device.
The hard mask pattern is typically patterned using a photoresist pattern, formed by a photolithography process including exposure and development processes, as an etch mask pattern or can be patterned by using another hard mask pattern, patterned using the above photoresist pattern as an etch mask pattern, as an etch mask pattern. In this case, there are limits to the fineness of the hard mask pattern and the patterns of the semiconductor device because of the resolution limit of exposure equipment.
Accordingly, for highly-integrated semiconductor devices, the hard mask pattern for patterning the patterns of the semiconductor device must be finer than the resolution of exposure equipment.